//动态标题
var OriginTitile = document.title
var titleTime
document.addEventListener('visibilitychange', function () {
  if (document.hidden) {
    //离开当前页面时标签显示内容
    document.title = '看不见我🙈~看不见我🙈~'
    clearTimeout(titleTime)
  } else {
    //返回当前页面时标签显示内容
    document.title = '♪(^∇^*)欢迎肥来！' + OriginTitile
    //两秒后变回正常标题
    titleTime = setTimeout(function () {
      document.title = OriginTitile
    }, 2000)
  }
})
